Verfahren zum Abschätzen der Bewegung in einem Bewegtbild

摘要

Correct motion estimation is performed by preventing an adverse effect due to the variation of lighting conditions when a motion estimation is performed in a motion image device. The method for estimating a motion by dividing an image frame represented by a luminance signal into a plurality of predetermined size blocks and detecting the most similar block in a previous frame with a block in a current frame and producing a corresponding movement distance as a motion vector, includes the steps of: producing a mean value of the luminance signal with regard to a block of the current frame; producing a mean value of the luminance signal with regard to a block to which a motion estimation of the previous frame is applied; compensating the luminance signal of the block to which the motion estimation of the previous frame is applied such that the two mean values have the same level; and selecting a block having the minimum sum of differences between luminance signals of each pixel, with regard to the block of the current frame and the block to which a motion estimation of the previous frame is applied, and producing the movement distance between these as a motion vector. Thus, a correct motion estimation can be made even when the light source is varied or a luminance signal is varied due to the moving of an object.